Skin cleansing formulations are generally well known in the art and typically include one or more active cleaning agents or detergents as well as any of several known antimicrobial agents to disinfect as well as cleanse the skin, particularly the hands. Other additives commonly used in such products include surfactants, foaming agents, solvents, thickening agents, moisturizers, vitamins, fragrances, and, as discussed herein, dyes or colorants.
Skin cleaning compositions are commonly found in kitchens, bathrooms and restrooms to be applied to the hands or skin of the user to cleanse or otherwise rid or disinfect the skin of any dirt, grime or germs which may be present on the hands or skin of the user. Today, many of these skin cleansers are liquid soaps and gel-like products which are readily accessible to the user by simply pouring, spraying or otherwise dispensing the product from a dispenser or other container mounted on a wall or placed on a countertop near the sink or other wash basin. These liquid products typically are of a color and fragrance that the user will associate with cleansing or with overall good health. For example, some soap products may be orange in color and have the fragrance of a orange, thereby appealing to the user's senses as providing a fruity, healthy product to the skin. Alternatively, some liquid skin cleansers may be pink in color wherein the user may associate that the product is offering some sort of medicinal quality. Of course, other colors associated with healthy products are also often employed.
Regardless of the color and fragrance employed, users such as children often attempt to use too much skin cleanser. As a result, excess skin cleanser is released from the dispenser and deposited on any of a variety of inanimate surfaces such as counters, floors, tiles and related fixtures. These surfaces can be made from any of a variety of materials including wood, marble, stone, ceramic, formica, and other well known composite materials. Unfortunately, these surfaces usually are not the same color as the skin cleanser. Thus, cleaning personnel are often wiping the counters, tiles, and fixtures to remove the excess skin cleanser that can be clearly seen on the surface due to the differences in color.
Where the excess skin cleanser is not removed over an extended period of time, a stain or unsightly residue may result. Skin cleansing compositions often contain compounds such as dyes or colorants which, if left untreated, may leave a stain or dark residue on certain surfaces. This is especially true of surfaces beneath fixed dispensers, where excess cleanser may drip onto the surface repeatedly before being removed.
Thus, a need exists for a skin cleanser that will not leave a colored residue on surfaces if the residue is left there for any appreciable amount of time.
Akin to this problem was the problem faced by surface cleaners. In that instance, the problem was that dyes were needed in the surface cleaner to visually determine and insure that a particular surface had been contacted by the cleaner and disinfectant. If the user did not remove all of the cleaner from the surface however, a colored residue would still remain. U.S. Pat. Nos. 4,965,063, 5,110,492, 5,057,303, and 5,064,635 all describe overcoming this problem by providing a cleaning composition for surfaces having a pH sensitive dye which includes a germicide and disappears upon exposure to air. While such a pH sensitive dye might be useful in a surface cleanser, it is not particularly useful in a skin cleansing composition since the dispensers currently employed in the skin cleansing industry are typically not airtight. Thus, the dye would disappear even before it is dispensed.
Photosensitive dyes are generally known in the art. These dyes have commonly been used to determine whether a product has been exposed to light so as to warn the user of a particular hazard. Moreover, the use of these dyes typically require that the dye change from a clear, transparent state to a colored state, thereby providing a visual warning to the user. The incorporation and use of a photosensitive dye in a skin cleanser is believed, heretofore, unknown.